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1.
Artigo em Inglês | MEDLINE | ID: mdl-38843116

RESUMO

RATIONAL: Ground glass opacities (GGO) in the absence of interstitial lung disease are understudied. OBJECTIVE: To assess the association of GGO with white blood cells (WBCs) and progression of quantified chest CT emphysema. METHODS: We analyzed data of participants in the Subpopulations and Intermediate Outcome Measures In COPD Study (SPIROMICS). Chest radiologists and pulmonologists labeled regions of the lung as GGO and adaptive multiple feature method (AMFM) trained the computer to assign those labels to image voxels and quantify the volume of the lung with GGO (%GGOAMFM). We used multivariable linear regression, zero-inflated negative binomial, and proportional hazards regression models to assess the association of %GGOAMFM with WBC, changes in %emphysema, and clinical outcomes. MEASUREMENTS AND MAIN RESULTS: Among 2,714 participants, 1,680 had COPD and 1,034 had normal spirometry. Among COPD participants, based on the multivariable analysis, current smoking and chronic productive cough was associated with higher %GGOAMFM. Higher %GGOAMFM was cross-sectionally associated with higher WBCs and neutrophils levels. Higher %GGOAMFM per interquartile range at visit 1 (baseline) was associated with an increase in emphysema at one-year follow visit by 11.7% (Relative increase; 95%CI 7.5-16.1%;P<0.001). We found no association between %GGOAMFM and one-year FEV1 decline but %GGOAMFM was associated with exacerbations and all-cause mortality during a median follow-up time of 1,544 days (Interquartile Interval=1,118-2,059). Among normal spirometry participants, we found similar results except that %GGOAMFM was associated with progression to COPD at one-year follow-up. CONCLUSIONS: Our findings suggest that GGOAMFM is associated with increased systemic inflammation and emphysema progression.

2.
Clin Shoulder Elb ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38738331

RESUMO

Overhead athletes undergo significant biomechanical adaptations due to repetitive overhead movements, primarily affecting the glenohumeral joint. These adaptations can lead to glenohumeral internal rotation deficit (GIRD), which is characterized by posterior capsule stiffness that results in glenohumeral joint translation and a shift in the center of gravity. The severity of GIRD is dependent upon the presence of asymmetry between gained external and lost internal rotation, which is defined clinically as an asymmetry exceeding 20º; this reduces the total range of motion compared to the unaffected limb or baseline measurements. Diagnosis is challenging, as it can be mistaken for chronic scapular adaptations. To mitigate misdiagnosis, a high clinical suspicion is crucial in overhead athletes, especially those who began performing forceful overhead movements before closure of growth plates. Periodic physical examinations should establish baseline values for glenohumeral rotation and track changes in glenohumeral motion to aid in diagnosis. Symptoms of GIRD include shoulder pain, stiffness, and decreased force exertion. Magnetic resonance imaging is the preferred imaging method for evaluating GIRD and assessing concomitant soft tissue pathologies. Untreated GIRD can lead to rotator cuff strength imbalances. Treatment mainly involves conservative measures, such as physical therapy, to improve internal rotation and alleviate posterior tightness. Surgical interventions are considered when symptoms persist despite conservative treatment with physical therapy or in the presence of concomitant pathologies.

3.
Ann Am Thorac Soc ; 21(7): 1022-1033, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38530051

RESUMO

Rationale: Rates of emphysema progression vary in chronic obstructive pulmonary disease (COPD), and the relationships with vascular and airway pathophysiology remain unclear. Objectives: We sought to determine if indices of peripheral (segmental and beyond) pulmonary arterial dilation measured on computed tomography (CT) are associated with a 1-year index of emphysema (EI; percentage of voxels <-950 Hounsfield units) progression. Methods: Five hundred ninety-nine former and never-smokers (Global Initiative for Chronic Obstructive Lung Disease stages 0-3) were evaluated from the SPIROMICS (Subpopulations and Intermediate Outcome Measures in COPD Study) cohort: rapid emphysema progressors (RPs; n = 188, 1-year ΔEI > 1%), nonprogressors (n = 301, 1-year ΔEI ± 0.5%), and never-smokers (n = 110). Segmental pulmonary arterial cross-sectional areas were standardized to associated airway luminal areas (segmental pulmonary artery-to-airway ratio [PAARseg]). Full-inspiratory CT scan-derived total (arteries and veins) pulmonary vascular volume (TPVV) was compared with small vessel volume (radius smaller than 0.75 mm). Ratios of airway to lung volume (an index of dysanapsis and COPD risk) were compared with ratios of TPVV to lung volume. Results: Compared with nonprogressors, RPs exhibited significantly larger PAARseg (0.73 ± 0.29 vs. 0.67 ± 0.23; P = 0.001), lower ratios of TPVV to lung volume (3.21 ± 0.42% vs. 3.48 ± 0.38%; P = 5.0 × 10-12), lower ratios of airway to lung volume (0.031 ± 0.003 vs. 0.034 ± 0.004; P = 6.1 × 10-13), and larger ratios of small vessel volume to TPVV (37.91 ± 4.26% vs. 35.53 ± 4.89%; P = 1.9 × 10-7). In adjusted analyses, an increment of 1 standard deviation in PAARseg was associated with a 98.4% higher rate of severe exacerbations (95% confidence interval, 29-206%; P = 0.002) and 79.3% higher odds of being in the RP group (95% confidence interval, 24-157%; P = 0.001). At 2-year follow-up, the CT-defined RP group demonstrated a significant decline in postbronchodilator percentage predicted forced expiratory volume in 1 second. Conclusions: Rapid one-year progression of emphysema was associated with indices indicative of higher peripheral pulmonary vascular resistance and a possible role played by pulmonary vascular-airway dysanapsis.


Assuntos
Progressão da Doença , Artéria Pulmonar , Enfisema Pulmonar , Tomografia Computadorizada por Raios X , Humanos , Masculino , Feminino , Enfisema Pulmonar/diagnóstico por imagem , Enfisema Pulmonar/fisiopatologia , Idoso , Pessoa de Meia-Idade , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/fisiopatologia , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Volume Expiratório Forçado , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem
4.
Front Nutr ; 11: 1371170, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38549749

RESUMO

Objective: There have been proposals that vitamin D may be associated with a reduction in the incidence of anxiety disorders. However, the findings thus far have been inconsistent, warranting further investigation. The purpose of this paper is to explore the link between serum vitamin D and anxiety. Methods: Data are from the National Health and Nutrition Examination Survey (NHANES) in the United States from 2007 to 2012. Study included a total of 12,232 participants, and through the multivariate logistic regression to study the relationship between serum vitamin D and anxiety, smooth curve fitting is used to study the nonlinear relationship between serum vitamin D levels and anxiety. Results: Serum vitamin D levels demonstrated a negative correlation with anxiety (p < 0.001). Vitamin D exhibited a significant impact on anxiety (Q4:OR = 0.774, 95% CI: 0.663-0.903, p < 0.01), and this effect remained significant even after adjusting for confounding variables (Q4:OR = 0.781, 95% CI: 0.669-0.912, p < 0.01). Smoothed curve fitting revealed a negative association between serum vitamin D levels and the risk of anxiety, and these findings persisted after accounting for confounding variables. Conclusion: Serum vitamin D levels were inversely associated with anxiety risk in US adults. In the future, more accurate prospective studies are needed to confirm this result.

5.
IEEE Trans Med Imaging ; 43(7): 2448-2465, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38373126

RESUMO

Chest computed tomography (CT) at inspiration is often complemented by an expiratory CT to identify peripheral airways disease. Additionally, co-registered inspiratory-expiratory volumes can be used to derive various markers of lung function. Expiratory CT scans, however, may not be acquired due to dose or scan time considerations or may be inadequate due to motion or insufficient exhale; leading to a missed opportunity to evaluate underlying small airways disease. Here, we propose LungViT- a generative adversarial learning approach using hierarchical vision transformers for translating inspiratory CT intensities to corresponding expiratory CT intensities. LungViT addresses several limitations of the traditional generative models including slicewise discontinuities, limited size of generated volumes, and their inability to model texture transfer at volumetric level. We propose a shifted-window hierarchical vision transformer architecture with squeeze-and-excitation decoder blocks for modeling dependencies between features. We also propose a multiview texture similarity distance metric for texture and style transfer in 3D. To incorporate global information into the training process and refine the output of our model, we use ensemble cascading. LungViT is able to generate large 3D volumes of size 320×320×320 . We train and validate our model using a diverse cohort of 1500 subjects with varying disease severity. To assess model generalizability beyond the development set biases, we evaluate our model on an out-of-distribution external validation set of 200 subjects. Clinical validation on internal and external testing sets shows that synthetic volumes could be reliably adopted for deriving clinical endpoints of chronic obstructive pulmonary disease.


Assuntos
Pulmão , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Pulmão/diagnóstico por imagem , Algoritmos , Radiografia Torácica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos
6.
Cell Rep Med ; 5(3): 101440, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38402622

RESUMO

Transmasculine people usually reach amenorrhea within 6 months of adequate testosterone treatment. It is often assumed that no ovulation occurs during amenorrhea. However, in this study, we report recent ovulatory activity in amenorrheic transmasculine people on testosterone therapy at gender-affirming oophorectomy. Histological signs of recent ovulatory activity, including the presence of ovulatory follicles, corpus luteum, and corpus albicans, are observed in 17 of 52 individuals (33%). This is not significantly correlated to the duration, testosterone serum levels, or type of testosterone used. These results suggest that amenorrhea does not equal anovulation in transmasculine people on adequate testosterone therapy, emphasizing the importance of contraception for people who engage in sexual activity that can result in pregnancy.


Assuntos
Amenorreia , Testosterona , Gravidez , Feminino , Humanos , Testosterona/uso terapêutico , Amenorreia/tratamento farmacológico , Ovulação
7.
Int J Mol Sci ; 24(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38069168

RESUMO

The reproductive lifespan in humans is regulated by a delicate cyclical balance between follicular recruitment and atresia in the ovary. The majority of the small antral follicles present in the ovary are progressively lost through atresia without reaching dominance, but this process remains largely underexplored. In our study, we investigated the characteristics of atretic small antral follicles and proposed a classification system based on molecular changes observed in granulosa cells, theca cells, and extracellular matrix deposition. Our findings revealed that atresia spreads in the follicle with wave-like dynamics, initiating away from the cumulus granulosa cells. We also observed an enrichment of CD68+ macrophages in the antrum during the progression of follicular atresia. This work not only provides criteria for classifying three stages of follicular atresia in small antral follicles in the human ovary but also serves as a foundation for understanding follicular degeneration and ultimately preventing or treating premature ovarian failure. Understanding follicular remodeling in the ovary could provide a means to increase the number of usable follicles and delay the depletion of the follicular reserve, increasing the reproductive lifespan.


Assuntos
Atresia Folicular , Ovário , Humanos , Feminino , Folículo Ovariano , Células da Granulosa , Células Tecais
8.
Sleep Adv ; 4(1): zpad036, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38152422
9.
J Virol ; 97(12): e0134323, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37975688

RESUMO

IMPORTANCE: Vaccinia virus infection requires virus-cell membrane fusion to complete entry during endocytosis; however, it contains a large viral fusion protein complex of 11 viral proteins that share no structure or sequence homology to all the known viral fusion proteins, including type I, II, and III fusion proteins. It is thus very challenging to investigate how the vaccinia fusion complex works to trigger membrane fusion with host cells. In this study, we crystallized the ectodomain of vaccinia H2 protein, one component of the viral fusion complex. Furthermore, we performed a series of mutational, biochemical, and molecular analyses and identified two surface loops containing 170LGYSG174 and 125RRGTGDAW132 as the A28-binding region. We also showed that residues in the N-terminal helical region (amino acids 51-90) are also important for H2 function.


Assuntos
Fusão de Membrana , Vaccinia virus , Proteínas Virais de Fusão , Internalização do Vírus , Vaccinia virus/química , Vaccinia virus/genética , Vaccinia virus/metabolismo , Proteínas Virais de Fusão/química , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/metabolismo
10.
J Chem Educ ; 100(11): 4279-4286, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38028751

RESUMO

All learners have a contribution to make to the development of the Chemical Sciences, be that in novel ways to teach, and their perspectives and contexts, but also in research, both in chemical education and the wider Chemical Sciences. Through four case studies, this paper explores interactions with diverse groups and how this has altered perspectives on both teaching and research. The case studies include work with visually impaired adults, a project bringing together First Peoples in Australia with academics to explore old ways (traditional science) and new ways (modern approaches), primary (elementary) school perspectives on teaching science, and a project in South Africa to connect university and township communities. Not only do these case studies demonstrate the immense value these diverse groups bring to our understanding about how to learn, but they also bring new perspectives on how to view and solve chemical problems.

11.
Res Sq ; 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37398360

RESUMO

Background: Despite advancements in checkpoint inhibitor-based immunotherapy, patients with advanced melanoma who have progressed on standard dose ipilimumab (Ipi) + nivolumab continue to have poor prognosis. Several studies support a dose-response activity of Ipi, and one promising combination is Ipi 10mg/kg (Ipi10) + temozolomide (TMZ). Methods: We performed a retrospective cohort analysis of patients with advanced melanoma treated with Ipi10+TMZ in the immunotherapy refractory/resistant setting (n = 6), using similar patients treated with Ipi3+TMZ (n = 6) as comparison. Molecular profiling by whole exome sequencing (WES) and RNA-seq of tumors harvested through one responder's treatment was performed. Results: With a median follow up of 119 days, patients treated with Ipi10+TMZ had statistically significant longer median progression free survival of 144.5 days (range 27-219) vs 44 (26-75) in Ipi3+TMZ, p=0.04, and a trend for longer median overall survival of 154.5 days (27-537) vs 89.5 (26-548). All patients in the Ipi10 cohort had progressed on prior Ipi+Nivo. WES revealed only 12 shared somatic mutations including BRAF V600E. RNA-seq showed enrichment of inflammatory signatures, including interferon responses in metastatic lesions after standard dose Ipi + nivo and Ipi10 + TMZ compared to the primary tumor, and downregulated negative immune regulators including Wnt and TGFb signaling. Conclusion: Ipi10+TMZ demonstrated efficacy including dramatic responses in patients with advanced melanoma refractory to prior Ipi + anti-PD1, even with CNS metastases. Molecular data suggest a potential threshold of Ipi dose for activation of sufficient anti-tumor immune response, and higher dose Ipi is required for some patients.

12.
Front Radiol ; 3: 1088068, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37492389

RESUMO

Convolutional neural networks (CNNs) have been successfully applied to chest x-ray (CXR) images. Moreover, annotated bounding boxes have been shown to improve the interpretability of a CNN in terms of localizing abnormalities. However, only a few relatively small CXR datasets containing bounding boxes are available, and collecting them is very costly. Opportunely, eye-tracking (ET) data can be collected during the clinical workflow of a radiologist. We use ET data recorded from radiologists while dictating CXR reports to train CNNs. We extract snippets from the ET data by associating them with the dictation of keywords and use them to supervise the localization of specific abnormalities. We show that this method can improve a model's interpretability without impacting its image-level classification.

14.
Afr J Disabil ; 12: 1116, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152420

RESUMO

Background: Ensuring quality in the structure and process of stroke rehabilitation helps to attain a good outcome. However, knowledge on this is limited in resource-constrained settings such as Ghana. Objectives: This study aimed to explore healthcare professionals' (HCPs) views and experiences of the structure and process of stroke rehabilitation in three selected hospitals in Ghana. Method: A qualitative study was carried out involving 26 HCPs directly involved in stroke rehabilitation from three selected hospitals in the Greater Accra Region of Ghana representing the different levels of healthcare. Interviews were conducted using an interview guide to understand participants' views and experiences of the structure and process of stroke rehabilitation. Interview transcripts were analysed using thematic analysis. Results: HCPs reported limitations with the structure of stroke rehabilitation with regards to the availability of rehabilitation units, bed capacity, approach to care, availability of protocol, staff capacity development and payment systems. With respect to the process of rehabilitation, the primary and secondary level hospitals were found not to have computed tomography (CT) and magnetic resonance imaging (MRI) scanning equipment. Participants also reported limitations with discharge planning, basis for discharge and post-discharge care across all three hospitals. Conclusion: This study found limitations in the current structure and process of stroke rehabilitation, which when given some considerations for improvement, can help improve the quality of care and thereby improve the outcome of stroke patients in Ghana. Contribution: This study provided data which helps to assess the quality of stroke rehabilitation in Ghana.

15.
Pattern Recognit ; 1392023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37089791

RESUMO

Adversarial training, especially projected gradient descent (PGD), has proven to be a successful approach for improving robustness against adversarial attacks. After adversarial training, gradients of models with respect to their inputs have a preferential direction. However, the direction of alignment is not mathematically well established, making it difficult to evaluate quantitatively. We propose a novel definition of this direction as the direction of the vector pointing toward the closest point of the support of the closest inaccurate class in decision space. To evaluate the alignment with this direction after adversarial training, we apply a metric that uses generative adversarial networks to produce the smallest residual needed to change the class present in the image. We show that PGD-trained models have a higher alignment than the baseline according to our definition, that our metric presents higher alignment values than a competing metric formulation, and that enforcing this alignment increases the robustness of models.

16.
Reprod Biomed Online ; 47(1): 94-101, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37095040

RESUMO

RESEARCH QUESTION: What are the outcomes and experiences of oocyte vitrification treatment in trans masculine individuals (TMI) before and after testosterone use? DESIGN: This retrospective cohort study was conducted at the Amsterdam UMC in the Netherlands between January 2017 and June 2021. The TMI who had completed an oocyte vitrification treatment were consecutively approached for participation. Informed consent was provided by 24 individuals. Participants (n = 7) who initiated testosterone therapy were advised to stop 3 months before stimulation. Demographic characteristics and oocyte vitrification treatment data were retrieved from medical records. Evaluation of the treatment was collected via an online questionnaire. RESULTS: The median age of participants was 22.3 years (interquartile range 21.1-26.0) and mean body mass index was 23.0 kg/m2 (SD 3.2). After ovarian hyperstimulation, a mean of 20 oocytes (SD 7) were retrieved and a mean of 17 oocytes (SD 6) could be vitrified. Aside from a lower cumulative FSH dose, there were no significant differences between the prior testosterone users and testosterone naïve TMI. The overall satisfaction of oocyte vitrification treatment in participants was high. Hormone injections were considered the most strenuous part of treatment by 29% of participants, closely followed by oocyte retrieval (25%). CONCLUSIONS: No difference in response to ovarian stimulation was found for oocyte vitrification treatment between the prior testosterone users and testosterone naïve TMI. The questionnaire identified hormone injections as the most burdensome aspect of oocyte vitrification treatment. This information can be used to improve gender sensitive fertility counselling and fertility treatment strategies.


Assuntos
Preservação da Fertilidade , Vitrificação , Criopreservação/métodos , Preservação da Fertilidade/métodos , Estudos Retrospectivos , Oócitos/fisiologia , Recuperação de Oócitos , Testosterona/uso terapêutico
17.
S Afr J Physiother ; 79(1): 1839, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36873961

RESUMO

Background: Return to pre-stroke life is of great importance to stroke survivors, their families and communities as stroke affects their ability to perform activities of daily living. It is therefore important to understand the impact of stroke rehabilitation on the community life of stroke survivors in Ghana as there are limited data. Objectives: Our study aimed to explore and describe the views of stroke survivors on the impact of stroke rehabilitation on their community life. Method: A descriptive qualitative study was conducted among 15 stroke survivors recruited from three selected hospitals in the Greater Accra Region of Ghana. Individual in-depth interviews were conducted using a semi-structured interview guide. Interview transcripts were analysed using thematic analysis and this gave rise to several themes. Results: The authors found that stroke left most of the survivors with functional limitations and they required various degrees of assistance to perform their activities of daily living. As the stroke survivors received rehabilitation, most of them mentioned improvements in function. However, most participants were still unable to return to work and enjoy social or leisure activities. Conclusion: Our study shows that attention needs to be given to the occupational and social management in rehabilitation as much as it is given to the physical management, to improve community integration post-stroke. Clinical implications: Our study highlights the need to take into consideration the occupational and social aspects of life as part of the rehabilitation process for stroke survivors.

18.
Nutrients ; 15(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36904261

RESUMO

Predictors of healthy eating parameters, including the Healthy Eating Index (HEI), Glycemic Index (GI), and Glycemic Load (GL), were examined using various modern diets (n = 131) in preparation for personalized nutrition in the e-health era. Using Nutrition Data Systems for Research computerized software and artificial intelligence machine-learning-based predictive validation analyses, we included domains of HEI, caloric source, and various diets as the potentially modifiable factors. HEI predictors included whole fruits and whole grains, and empty calories. Carbohydrates were the common predictor for both GI and GL, with total fruits and Mexican diets being additional predictors for GI. The median amount of carbohydrates to reach an acceptable GL < 20 was predicted as 33.95 g per meal (median: 3.59 meals daily) with a regression coefficient of 37.33 across all daily diets. Diets with greater carbohydrates and more meals needed to reach acceptable GL < 20 included smoothies, convenient diets, and liquids. Mexican diets were the common predictor for GI and carbohydrates per meal to reach acceptable GL < 20; with smoothies (12.04), high-school (5.75), fast-food (4.48), Korean (4.30), Chinese (3.93), and liquid diets (3.71) presenting a higher median number of meals. These findings could be used to manage diets for various populations in the precision-based e-health era.


Assuntos
Carga Glicêmica , Telemedicina , Índice Glicêmico , Dieta Saudável , Inteligência Artificial , Dieta , Glicemia , Carboidratos da Dieta
19.
iScience ; 26(4): 106320, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-36968078

RESUMO

HER2-targeted therapy has improved breast cancer survival, but treatment resistance and disease prevention remain major challenges. Genes that enable HER2/Neu oncogenesis are the next intervention targets. A bioinformatics discovery platform of HER2/Neu-expressing Diversity Outbred (DO) F1 Mice was established to identify cancer-enabling genes. Quantitative Trait Loci (QTL) associated with onset ages and growth rates of spontaneous mammary tumors were sought. Twenty-six genes in 3 QTL contain sequence variations unique to the genetic backgrounds that are linked to aggressive tumors and 21 genes are associated with human breast cancer survival. Concurrent identification of TSC22D3, a transcription factor, and its target gene LILRB4, a myeloid cell checkpoint receptor, suggests an immune axis for regulation, or intervention, of disease. We also investigated TIEG1 gene that impedes tumor immunity but suppresses tumor growth. Although not an actionable target, TIEG1 study revealed genetic regulation of tumor progression, forming the basis of the genetics-based discovery platform.

20.
Lancet Digit Health ; 5(2): e83-e92, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36707189

RESUMO

BACKGROUND: Quantitative CT is becoming increasingly common for the characterisation of lung disease; however, its added potential as a clinical tool for predicting severe exacerbations remains understudied. We aimed to develop and validate quantitative CT-based models for predicting severe chronic obstructive pulmonary disease (COPD) exacerbations. METHODS: We analysed the Subpopulations and Intermediate Outcome Measures In COPD Study (SPIROMICS) cohort, a multicentre study done at 12 clinical sites across the USA, of individuals aged 40-80 years from four strata: individuals who never smoked, individuals who smoked but had normal spirometry, individuals who smoked and had mild to moderate COPD, and individuals who smoked and had severe COPD. We used 3-year follow-up data to develop logistic regression classifiers for predicting severe exacerbations. Predictors included age, sex, race, BMI, pulmonary function, exacerbation history, smoking status, respiratory quality of life, and CT-based measures of density gradient texture and airway structure. We externally validated our models in a subset from the Genetic Epidemiology of COPD (COPDGene) cohort. Discriminative model performance was assessed using the area under the receiver operating characteristic curve (AUC), which was also compared with other predictors, including exacerbation history and the BMI, airflow obstruction, dyspnoea, and exercise capacity (BODE) index. We evaluated model calibration using calibration plots and Brier scores. FINDINGS: Participants in SPIROMICS were enrolled between Nov 12, 2010, and July 31, 2015. Participants in COPDGene were enrolled between Jan 10, 2008, and April 15, 2011. We included 1956 participants from the SPIROMICS cohort who had complete 3-year follow-up data: the mean age of the cohort was 63·1 years (SD 9·2) and 1017 (52%) were men and 939 (48%) were women. Among the 1956 participants, 434 (22%) had a history of at least one severe exacerbation. For the CT-based models, the AUC was 0·854 (95% CI 0·852-0·855) for at least one severe exacerbation within 3 years and 0·931 (0·930-0·933) for consistent exacerbations (defined as ≥1 acute episode in each of the 3 years). Models were well calibrated with low Brier scores (0·121 for at least one severe exacerbation; 0·039 for consistent exacerbations). For the prediction of at least one severe event during 3-year follow-up, AUCs were significantly higher with CT biomarkers (0·854 [0·852-0·855]) than exacerbation history (0·823 [0·822-0·825]) and BODE index 0·812 [0·811-0·814]). 6965 participants were included in the external validation cohort, with a mean age of 60·5 years (SD 8·9). In this cohort, AUC for at least one severe exacerbation was 0·768 (0·767-0·769; Brier score 0·088). INTERPRETATION: CT-based prediction models can be used for identification of patients with COPD who are at high risk of severe exacerbations. The newly identified CT biomarkers could potentially enable investigation into underlying disease mechanisms responsible for exacerbations. FUNDING: National Institutes of Health and the National Heart, Lung, and Blood Institute.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Qualidade de Vida , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Volume Expiratório Forçado , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Biomarcadores , Tomografia Computadorizada por Raios X
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